Who's taping whom?

As Angela Coppola stood on a sidewalk and pointed her silver mini-digital camera at a New York City police officer, he turned his video camera right back on her.

Ms. Coppola, an antiwar activist, says she was simply exercising her right to videotape the demonstrations held during the Republican National Convention. But the police officer, she argues, was overstepping his bounds.

"It's a form of intimidation. Why should they be monitoring us for doing this?" asks Coppola, a member of the No RNC Clearinghouse, a group organized to facilitate protests during the convention.

Widespread use of digital cameras at both large demonstrations and small antiwar rallies raises serious questions about intimidation, civil rights, and privacy. Should police be able to record peaceful demonstrators? Are activists using cameras to antagonize police? As the technology becomes more pervasive, its limits are being tested in courts and questioned by civil libertarians.

Growing numbers of "video activists" say cameras protect their rights and help spread their messages. Filming a demonstration, they say, lessens the possibility of police abuse and, if abuse occurs, the tape becomes evidence.

But police, too, are attempting to protect their rights. They use video in the event protests turn violent, to investigate crimes afterward, and to transmit images through wireless cameras to police command centers. They use it for training and, they say, to investigate groups that may have links to terrorist organizations.

Now that the RNC protests are over, the efficacy of videotaping will be tested. With about 1,800 arrests during several days of protests, footage of those demonstrations is being collected and cataloged by groups like the National Lawyers Guild. Much of it will be evidence in court.

"There is a huge amount of power in these videos in terms of protecting the First Amendment," says Alan Graf, a National Lawyers Guild attorney and activist from Portland, Ore., who used video evidence in a class-action lawsuit against the city of Portland over a 2002 protest that went awry. "Normally it's [the police's] word against a scruffy protester, and the protester loses," says Mr. Graf. "This is the new tool to protect the Bill of Rights."

Filming protests of every ilk is nothing new. Documentarians have been doing this for decades. The United Mine Workers and the AFL-CIO have long used film to document strikes. Police departments and the FBI, too, routinely photograph, videotape, and conduct surveillance of radical groups.

"The camera can be a witness, and also be a deterrent," says A. Mark Liiv, a documentary filmmaker and member of Whispered Media, a San Francisco video activist collective. Mr. Liiv has been documenting political demonstrations and environmentalist actions since the mid-1990s. Today, he says, "Video is so prevalent at demonstrations" that about 1 in every 10 protesters at the protests in New York carried some kind of digital camera.

Laws pertaining to the use of video by police vary by state and are hotly debated, says Bruce Bentley of the New York chapter of the National Lawyers Guild.

The New York City Police Department, the largest law-enforcement agency in the country, is bound by a federal court decree - the Handschu agreement - which originally provided that there can't be any investigation of political groups when a crime isn't present, says Franklin Siegel, a New York civil rights attorney.

"Basically it said you can't take video or photographs of demonstrators 'until the first fist flies,' and that stood for many, many years," he says. But the decree - named for a 1985 class-action lawsuit brought against the police for using surveillance on activists - was modified in March 2003 after the department went to court arguing it needed more flexibility to investigate terrorist-related cases.

One new provision - which Mr. Siegel says is probably going to be challenged in court - allows the police to attend any public event as a member of the public. "What the police have taken that to mean is that they can photograph and videotape with impunity," says Siegel. "We are going to be moving to prevent the police from using these relaxed standards ... in the context of First Amendment activity."

The US district court judge who approved the department's request to amend the Handschu decree concluded that the provision was outdated and limited the NYPD's ability to investigate possible terrorist threats.

The relaxed guidelines allowed police to videotape political activity throughout the RNC protests, but a spokesman for the New York City Police Department says that police used video cameras only when they felt the demonstrations might turn violent. "There is no intent to intimidate anyone," he says.

It's intimidating to protesters to be videotaped by a police officer, says Sidney Tarrow, professor of government and sociology at Cornell University. But "that intimidation has limits," he adds. One police officer with a video camera at a massive protest does not amount to intimidation, he insists.

The rise in video activism is only one way technology is altering social movements. Cheap and accessible, digital technology - like text messaging through mobile phones - has enabled activists worldwide to organize on the Internet.

Activists have taken advantage of the convergence of technologies "more successfully than any other group in society," says Lance Bennett, political science professor and director of the Center for Communication and Civic Engagement at the University of Washington.

In Manila in 2001, mass protests that eventually brought down Philippine President Joseph Estrada were organized using text messaging over mobile phones. When President Bush traveled to London in November 2003 antiwar activists who organized roving "Chasing Bush" protests relied on text messages and the Internet.

"Protesters have a large-scale communication medium at their service for the first time in history," says Mr. Bennett. "That's a tremendous advantage."

But this "could turn out to be a cloud with a black lining," says Tarrow. Now that the revolution has been pixilated, downloaded, edited, posted on the Internet, it can reach anyone with a computer - including police officers, government agencies, and opposition groups.